Social conservatives in Delaware have begun a campaign to defeat a measure that would offer gay and lesbian couples many of the benefits and responsibilities of marriage.

The gay rights group Equality Delaware announced last month that it was helping lawmakers draft legislation to legalize civil unions in the state. The measure is expected to be introduced sometime this month.

In an “Urgent call to action,” the Delaware Family Policy Council urged members to oppose the proposal.

“A vote for civil unions is a vote for same-sex 'marriage' because civil unions are a springboard to redefining marriage,” the group said, referring to instances – for example in Illinois – in which activists called for marriage equality after lawmakers approved civil unions. “Therefore, civil unions are a desperate and dishonest attempt to force same-sex 'marriage' on Delaware.”

“If government changes the definition of marriage, which civil unions will do, it will have to enforce the belief that same sex 'marriage' is the equivalent of man/woman marriage. This belief will be taught in the classroom.”

In its message, the group also targeted three Republicans – Joseph Miro, Nick Manolakos and Michael Ramone – and three Democrats – Quinton Johnson, Earl Jaques Jr. and Rebecca Walker – seen as possible supporters of the measure.

If Delaware approves civil unions, the state would join Illinois, Hawaii and New Jersey in offering the union. Colorado lawmakers are also debating the issue.